Ceramics base plate and method for producing the same

Abstract

A method of producing ceramics base plates is disclosed, comprising forming a continuous flaw on at least one surface of a ceramics sintered base plate from end to end using a flawing tool and dividing the ceramics sintered base plate along the flaw by applying an external force. It is preferred that a blade edge portion of the flawing tool is made of a cemented carbide or diamond. By the method of the invention, the ceramics sintered base plate can be easily divided, and ceramics base plates excellent in dimensional accuracy are obtained without lowering the strength thereof.

1. A method of producing ceramics base plates, which comprises:
 forming a continuous flaw up to a depth of {fraction (1/10)} of the thickness of the ceramics sintered base plate on at least one surface of the ceramics sintered base plate from end to end using a flawing tool; and  
 dividing the ceramics sintered base plate along the flaw by applying an external force, wherein a blade edge portion of the flawing tool is made of a cemented carbide or diamond.  
 
   
   
     2. A method of producing ceramics base plates as claimed in  claim 1 , wherein the blade edge portion of the flawing tool is made of diamond. 
   
   
     3. A method of producing ceramics base plates as claimed in  claim 1 , comprising forming the continuous flaw to a depth of from {fraction (1/100)} to {fraction (1/10)} of the thickness of the ceramics sintered base plate. 
   
   
     4. A method of producing ceramics base plates as claimed in  claim 1 , wherein Vickers hardness of the ceramics sintered base plate is 1,500 Hv or lower. 
   
   
     5. A method of producing ceramics base plates as claimed in  claim 1 , wherein the ceramics sintered base plate is an aluminum nitride sintered base plate. 
   
   
     6. A method of producing ceramics base plates as claimed in  claim 1 , wherein a cooling medium is not used at forming the flaw on the surface of the ceramics sintered base plate and at dividing the ceramics sintered base plate.